projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 174cd4b1 | 2 | #include <linux/sched/signal.h> |
| 29930025 | 3 | #include <linux/sched/task.h> |
| 68db0cf1 | 4 | #include <linux/sched/task_stack.h> |
| 5a0e3ad6 | 5 | #include <linux/slab.h> |
| 0ea820cf PM |
6 | #include <asm/processor.h> |
| 7 | #include <asm/fpu.h> | |
| f03c4866 | 8 | #include <asm/traps.h> |
| 4cf421e5 | 9 | #include <asm/ptrace.h> |
| 0ea820cf PM |
10 | |
| 11 | int init_fpu(struct task_struct *tsk) | |
| 12 | { | |
| 13 | if (tsk_used_math(tsk)) { | |
| 14 | if ((boot_cpu_data.flags & CPU_HAS_FPU) && tsk == current) | |
| 15 | unlazy_fpu(tsk, task_pt_regs(tsk)); | |
| 16 | return 0; | |
| 17 | } | |
| 18 | ||
| 19 | /* | |
| 20 | * Memory allocation at the first usage of the FPU and other state. | |
| 21 | */ | |
| 22 | if (!tsk->thread.xstate) { | |
| 23 | tsk->thread.xstate = kmem_cache_alloc(task_xstate_cachep, | |
| 24 | GFP_KERNEL); | |
| 25 | if (!tsk->thread.xstate) | |
| 26 | return -ENOMEM; | |
| 27 | } | |
| 28 | ||
| 29 | if (boot_cpu_data.flags & CPU_HAS_FPU) { | |
| 30 | struct sh_fpu_hard_struct *fp = &tsk->thread.xstate->hardfpu; | |
| 31 | memset(fp, 0, xstate_size); | |
| 32 | fp->fpscr = FPSCR_INIT; | |
| 33 | } else { | |
| 34 | struct sh_fpu_soft_struct *fp = &tsk->thread.xstate->softfpu; | |
| 35 | memset(fp, 0, xstate_size); | |
| 36 | fp->fpscr = FPSCR_INIT; | |
| 37 | } | |
| 38 | ||
| 39 | set_stopped_child_used_math(tsk); | |
| 40 | return 0; | |
| 41 | } | |
| 42 | ||
| 43 | #ifdef CONFIG_SH_FPU | |
| 44 | void __fpu_state_restore(void) | |
| 45 | { | |
| 46 | struct task_struct *tsk = current; | |
| 47 | ||
| 48 | restore_fpu(tsk); | |
| 49 | ||
| 50 | task_thread_info(tsk)->status |= TS_USEDFPU; | |
| 616c05d1 | 51 | tsk->thread.fpu_counter++; |
| 0ea820cf PM |
52 | } |
| 53 | ||
| 54 | void fpu_state_restore(struct pt_regs *regs) | |
| 55 | { | |
| 56 | struct task_struct *tsk = current; | |
| 57 | ||
| 58 | if (unlikely(!user_mode(regs))) { | |
| 59 | printk(KERN_ERR "BUG: FPU is used in kernel mode.\n"); | |
| 60 | BUG(); | |
| 61 | return; | |
| 62 | } | |
| 63 | ||
| 64 | if (!tsk_used_math(tsk)) { | |
| 4291b730 | 65 | local_irq_enable(); |
| 0ea820cf PM |
66 | /* |
| 67 | * does a slab alloc which can sleep | |
| 68 | */ | |
| 69 | if (init_fpu(tsk)) { | |
| 70 | /* | |
| 71 | * ran out of memory! | |
| 72 | */ | |
| 73 | do_group_exit(SIGKILL); | |
| 74 | return; | |
| 75 | } | |
| 4291b730 | 76 | local_irq_disable(); |
| 0ea820cf PM |
77 | } |
| 78 | ||
| 79 | grab_fpu(regs); | |
| 80 | ||
| 81 | __fpu_state_restore(); | |
| 82 | } | |
| 83 | ||
| 84 | BUILD_TRAP_HANDLER(fpu_state_restore) | |
| 85 | { | |
| 86 | TRAP_HANDLER_DECL; | |
| 87 | ||
| 88 | fpu_state_restore(regs); | |
| 89 | } | |
| 90 | #endif /* CONFIG_SH_FPU */ |